Thermostatic Mixing Valve

Thermostatic Mixing Valves for Safe Hot Water Temperatures

T&D offer a wide range thermostatic mixing valves and can provide next day deliveries from stock on mixing valves from Reliance Water Controls.

Thermostatic mixing valves help to resolve conflicting issues from storing and circulating hot water at a temperature too low allowing legionella bacteria to grow and too hot resulting in scalding.

TMV's work by blending hot water with cold water at the point of use to provide a constant safe output temperature, allowing the hot water to be stored and circulated at higher temperatures to kill or disinfect legionella bacteria.

Thermostatic Mixing Valves, Legionella & Burns

Legionella can grow in any water system if it not properly maintained and Legionnaire's Disease can develop from small droplets of contaminated legionella bacteria.

Legionnaire's Disease can be especially dangerous to children and the elderly.

How Temperature Effects Legionella Bacteria

Temperature Range

Effect

70-80ºC

Disinfection range

66ºC

Legionella will die in 2 minutes

60ºC

Legionella will die in 32 minutes

55ºC

Legionella will die in 5-6 hours

50-55ºC

Legionella will survive but does not multiply

20-50ºC

Legionella bacteria will grow

Below 20ºC

Legionella will be dormant but will survive

Legionella can be eradicated by a number of different methods, each with their own disadvantages.

The water supply can be treated with chlorine which poses a number of issues if the water system is in use, alternatively heating the water above 70ºC for 30 minutes but this can be dangerous is temperature controls are not in use.

High temperatures can quickly result in burns and scalding, with children, the elderly and disabled being at higher risk.

Higher temperatures result in burns and scalds quicker and more severe, temperatures below 50ºC can be considered safer, allowing the user, whether that be a child or an elderly adult sufficient time to react but these temperatures allowing legionella bacteria to grow rapidly increasing risk of Legionnaire's Disease.

Thermostatic mixing valves resolve these issues and typically result in output temperatures between 38ºC and 44ºC and have an auto shut off safety feature in the event the hot or cold water supply is interrupted or stopped.